The story about how secure boot for Windows 8, part of UEFI, will hinder the use of non-signed binaries and operating systems, like Linux, has registered at Redmond as well. The company posted about it on the Building Windows 8 blog - but didn't take any of the worries away. In fact, Red Hat's Matthew Garrett, who originally broke this story, has some more information - worst of which is that Red Hat has received confirmation from hardware vendors that some of them will not allow you to disable secure boot.

Macs don't require the use secure boot, do they? They prevent the OS from booting on non Apple hardware, but that's different: its limiting the use of their software. Microsoft limits the use of the hardware that works with their software. I think Microsoft's is much worse. Software is usually cheaper than hardware.